package com.eatme.leetcode.problems;

import java.util.TreeMap;

/**
 * 211. 添加与搜索单词 - 数据结构设计 - design-add-and-search-words-data-structure
 */
class WordDictionary211 {

    public class Node {
        public boolean isWord;
        private TreeMap<Character, Node> next;

        public Node(boolean isWord) {
            this.isWord = isWord;
            next = new TreeMap<>();
        }

        public Node() {
            this(false);
        }
    }

    private Node root;

    public WordDictionary211() {
        root = new Node();
    }
    
    public void addWord(String word) {
        Node cur = root;
        for (int i = 0; i < word.length(); i++) {
            char c = word.charAt(i);
            if (cur.next.get(c)==null)
                cur.next.put(c,new Node());
            cur = cur.next.get(c);
        }
        cur.isWord =true;
    }
    
    public boolean search(String word) {
        return match(root,word,0);
    }

    private boolean match(Node node,String word,int index) {
        if (index==word.length())
            return node.isWord;
        char c = word.charAt(index);
        if (c!='.') {
            if (node.next.get(c)==null)
                return false;
            return match(node.next.get(c),word,index+1);
        }else
            for (char nextChar: node.next.keySet())
                if (match(node.next.get(nextChar),word,index+1))
                    return true;
            return false;
    }
}

/**
 * Your WordDictionary object will be instantiated and called as such:
 * WordDictionary obj = new WordDictionary();
 * obj.addWord(word);
 * boolean param_2 = obj.search(word);
 */